NRG Energy, the power producer and retail electric provider, notified the state’s grid manager the Electric Reliability Council of Texas that it is retiring two generating units in La Porte that became too outdated and inefficient to continue to operate.

The units at the SR Bertron natural gas-fired generation station were mothballed in 2013 and neither has operated in five years. The two units were capable producing 292 megawatts of power. A megawatt is enough to power about 200 Texas homes on a hot summer day.

Two other units at the site were retired last year, said NRG spokesman David Knox. All together, the four units generated about 714 megawatts.